Gravitational Waves Observed

[Hashi Lebwohl]

Back in August, astronomers had a chance to observe two neutron stars colliding; the results of this collision produced both gravitational waves as well as light, giving them more information that they had been able to gather from previous observations. Among the early analysis of the data is confirmation that gravitational waves propagate at the speed of light, that gamma ray bursts can occur from neutron star collisions, and spectral analysis shows the presence of heavier elements such as gold.

[Zarathustra]

When gravity waves were first detected in 2015, they predicted that it would usher in a new age of astronomy. I guess we're seeing the beginning of that with this unprecedented observation. I don't know if we would have seen it in time if not for the warning we got in gravity waves, alerting scientists worldwide that something big had just happened in the universe. They were able to scramble Swift Gamma Ray Burst Explorer (a NASA satellite) within 16 minutes to catch ultraviolet radiation.

This was the first time gravity waves were observed along with electromagnetic radiation of the corresponding event, allowing inferences not possible otherwise--including the confirmation that they were in fact two neutron stars. I've heard it described as a "Rosetta Stone" of astrophysics, for this reason. Going back and looking at evidence from the Fermi gamma ray telescope (another satellite), we've found that the electromagnetic radiation arrived 1.7 seconds after the gravity waves. While this may only indicate intervening matter slowing it down (rather than gravity waves travelling faster than light), it allows us to make inferences on the intervening stuff based on the time difference. We have a baseline with the gravity waves to gauge everything else.

It finally confirmed a theory for the formation of heavier elements, gold, platinum, and uranium having been observed in the process of formation.

It allowed for a revised measurement of the expansion of the universe.

It confirmed a theory for the cause of gamma ray bursts.

It allowed us to test theories for the "squishiness" of neutron stars.

This is a big damn deal.

[Hashi Lebwohl]

Exactly. The first papers are only now being published; the data collected from this 100-second-long observation will find their way into journals for the next several years.

It makes sense that gravity waves are not affected by gravity itself (other than probably following the curvature)--photons being emitted from a star are slowed down as they are pulled back towards the star (but not by much).

[Vraith]

Yea, it's an exponential big damn deal. Cuz we learned a lot of crap...and could keep learning more...as things are.
But the gravity gear is now going down for upgrades. A year from now or so, it will be like swapping your opera glasses, and "dear diary" records for a telescope backed by HD vid and audio.

hashi...it's not just that photons are slowed. It's ALSO that that and other info continues for a while, but not a causally-observable while, after the collision...so we can react quickly enough to SEE the effects instead of depending on luck and/or theoretical calculations. [[I'm sure as fuck you know that...but I wanted to say it....then realized Z already included it, but I didn't feel like deleting this part.]].

[Hashi Lebwohl]

A handful of new events have recently been detected, all thanks to gravity waves: a neutron star colliding with a black hole, two neutron stars colliding, and a potential merger among three black holes.

[Cord Hurn]

The black hole at the center of galaxy M87, about 55 million light-years away, gives further confirmation to Einstein's theory of relativity. https://www.sciencenews.org/article/eve ... relativity

[Cord Hurn]

"Black hole revelations win the 2020 Nobel Prize in physics"

https://www.sciencenews.org/article/phy ... ndrea-ghez